Edged tools represented by surgical blade (scalpel, etc.) and shaving razor preferably have high sharpness of their edges.
The following proposals have been made on these sorts of edged tools.
For example, Patent Literature 1 describes a blade member which includes edges of a group of blades subjected to ion beam treatment using a plasma ion gun in a vacuum chamber, in which argon is used as a medium, wherein the pressure of the argon gas is 0.1 to 1 Pa, a bias voltage applied to the blade group is 0.1 to 1000V, and the processing time is 5 to 300 minutes. According to the description, an edged tool with enhanced sharpness and clean cuttability was successfully provided by improving a processing technology based on ion beam processing.
In other example, Patent Literature 2 describes a method of surface modification of blade edges of sharp edge tools, wherein the method includes subjecting sharp metal edged tools to vacuum evaporation, while applying in vacuo negative voltage to the blade edges of sharp metal edged tools to cause ion implantation of anion on the surface of the blade edge. According to the description, such method successfully improves mechanical properties of the surgical layer of the blade edges.
In still other example, Patent Literature 3 proposes a method of shaping or reshaping a blade edge by removing a blade material from both sides of the blade edge, by sputtering using argon ion. It is also described that the shape of blade edge as a result of ion bombardment is given by W=ad″ (where, W represents the thickness of the blade edge measured at distance d away from the end of blade, and a and n are constants).
Again in still other example, Patent Literature 4 describes a technique of increasing hardness of an edged tool by forming on the surface thereof a hard layer composed of an intermetallic compound by plasma ion nitriding, or by forming on the surface a diamond-like carbon film, to thereby suppress wearing, and to prevent dulling.